Unindent rustc suggestion lines starting with '~' or '+'

Author: dtolnay

src/normalize.rs

@@ -63,6 +63,7 @@ normalizations! {
     UnindentMultilineNote,
     DependencyVersion,
     HeadingNote,
+    UnindentSuggestion,
     // New normalization steps are to be inserted here at the end so that any
     // snapshots saved before your normalization change remain passing.
 }
@@ -669,6 +670,14 @@ fn indented_line_kind(
     if spaces > 0
         && (rest == "|"
             || rest.starts_with("| ")
+            || normalization >= UnindentSuggestion
+                && digits > 0
+                && (rest == "~"
+                    || rest.starts_with("~ ")
+                    || rest == "+"
+                    || rest.starts_with("+ ")
+                    || rest == "-"
+                    || rest.starts_with("- "))
             || digits == 0
                 && (rest.starts_with("--> ") || rest.starts_with("::: ") || rest.starts_with("= ")))
     {

src/tests/ghost-note-help.rs

@@ -20,21 +20,21 @@ help: ensure that all possible cases are being handled by adding a match arm wit
    |
 " "
 error[E0004]: non-exhaustive patterns: `MyPhantom::__Phantom(_)` not covered
- --> src/main.rs:9:11
-  |
-9 |     match phantom {
-  |           ^^^^^^^ pattern `MyPhantom::__Phantom(_)` not covered
-  |
+  --> src/main.rs:9:11
+   |
+ 9 |     match phantom {
+   |           ^^^^^^^ pattern `MyPhantom::__Phantom(_)` not covered
+   |
 note: `MyPhantom<u8>` defined here
- --> src/main.rs:4:8
-  |
-3 | #[phantom]
-  | ---------- not covered
-4 | struct MyPhantom<T: ?Sized>;
-  |        ^^^^^^^^^
-  = note: the matched value is of type `MyPhantom<u8>`
+  --> src/main.rs:4:8
+   |
+ 3 | #[phantom]
+   | ---------- not covered
+ 4 | struct MyPhantom<T: ?Sized>;
+   |        ^^^^^^^^^
+   = note: the matched value is of type `MyPhantom<u8>`
 help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
-  |
+   |
 10 ~         MyPhantom => {},
 11 +         MyPhantom::__Phantom(_) => todo!()
    |